The standards for a clean room to manufacture a 1980s home computer CPU or modern lower-tech microcontroller are far, far less stringent that the clean rooms fo

The standards for a clean room to manufacture a 1980s home computer CPU or modern lower-tech microcontroller are far, far less stringent that the clean rooms for a 7nm or 10nm part. The photolithography equipment you need is far less precise and far more common. There are a lot more fab cranking out IoT device chips than Xeons.